This has changed, the S4 has been approved for Government use, more Samsung phones to follow:
http://www.cbsnews.com/8301-205_162...sung-galaxy-s4-for-its-networks-company-says/
Sorry but I work for the government and no it has not been approved throughout the whole system yet. Believe the news all you want but I work in the IS department. Plus unless they fix the ways to break through the security then I still do not see it being secure. And that is what we see.